JPH0663820U - Exhaust manifold - Google Patents

Abstract

(57) [Abstract] [Purpose] Regardless of the type of pipe used for the exhaust port side, the tip of the pipe can be easily processed, and an exhaust manifold with a good sealing property after the pipe is assembled is provided. To do. [Constitution] Port head 2 for cylinder head 1
Thus, the exhaust manifold 10 connecting the exhaust port side pipe 3 is provided with a return flange 4 which is a return line at least once at the tip of the exhaust port side pipe 3 and is thus an exhaust manifold.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an exhaust manifold of a type in which an exhaust port side pipe is connected to a cylinder head of an automobile or the like so as to be able to absorb thermal deformation.

[0002]

[Prior art]

 In the conventional structure for connecting the exhaust port side pipe of the exhaust manifold to the cylinder head by the port flange, the tip of the exhaust port side pipe 3 is initially welded to the port flange 2 as shown in FIG. Was. However, in this structure, the port flange and the pipe are directly welded, so there is a problem that the thermal deformation cannot be absorbed. As shown in Fig. 5, a flange-shaped seat portion is provided at the tip of the exhaust port side pipe 3. No. 7 is installed, and the spacer 5 is attached to the port flange 2 with a gap 5 therebetween to absorb thermal deformation (Actual No. 63-40519), or a flange-shaped seat by attaching a ring of another member. The part was designed to absorb thermal deformation as described above.

[0003]

[Problems to be solved by the device]

 With the structure in which the flange-shaped seat portion 7 is provided at the tip of the exhaust port side pipe 3 shown in FIG. 5 above, thermal deformation can be absorbed, but even if the spacer 8 is installed, There may be a problem with the sealing property between the two. Flatness is important for the seat portion 7 that is in close contact with the cylinder head. Therefore, for example, if an electric resistance welded pipe is used for the exhaust port side pipe 3, the seat portion 7 loses the flatness as shown by the chain double-dashed line in FIG. Therefore, it is necessary to use drawn pipes (seamless pipes) or tubular flat drawn products. The attachment of the ring requires a ring member which is a separate member, and an attachment process such as welding is also required.

The present invention provides an exhaust manifold which has a good end seal regardless of the type of pipe used for the exhaust port side pipe 3 and has a good sealing property after the pipe is assembled. Is what you are trying to do.

[0005]

[Means for Solving the Problems]

 The exhaust manifold of the present invention is an exhaust manifold in which the exhaust port side pipe 3 is connected to the cylinder head 1 by the port flange 2, and the return flange 4 which is at least one or more turns at the end of the exhaust port side pipe 3. Is provided.

[0006]

[Action]

 With such a structure, since the folding flange 4 is composed of the port flange contact side retaining portion 4a, the cylinder head contact side seat portion 4c and the folding elastic portion 4b between them, thermal deformation is prevented from occurring on the port flange contact side retaining portion. The seat portion 4c comes into close contact with the cylinder head 1 due to the elasticity of the folded elastic portion 4b, and the sealing performance is improved. This sealing property is not impaired even if an electric resistance welded pipe is used.

[0007]

【Example】

 FIG. 1 is a fragmentary plan view of a main part of an exhaust manifold of a first embodiment of the present invention, and FIG. 2 is an enlarged view of the main part. As is clear from these figures, the exhaust manifold 10 connects the exhaust port side pipe 3 to the cylinder head 1 having the exhaust port by using the port flange 2. In this structure, the return flange 4 is provided at the tip of the exhaust port side pipe 3. The folding flange 4 is folded once in this example, but it may be folded twice as in the second embodiment shown in FIG. 3, or may be folded further.

The relationship between the folded back flange 4 and the port flange 2 is such that the holding hole of the folded back flange 4 provided in the port flange 2 has a large diameter so that a gap 5 is formed. This is the same as before. However, since the folding flange 4 is composed of the port flange contact side retaining portion 4a, the cylinder head contact side seat portion 4c and the folding elastic portion 4b therebetween, thermal deformation is absorbed by the port flange contact side retaining portion 4a, and the folding back is performed. Due to the elasticity of the elastic portion 4b, the seat portion 4c is in close contact with the cylinder head 1 and has a good sealing property.

In the exhaust manifold, there are a case where all ports are movable as shown in FIG. 1 to absorb thermal deformation, and a case where a pipe is movable only for an arbitrary port. The present invention can be implemented in any of these cases, and also when the port flange is a split type.

[0010]

[Effect of device]

 According to the present invention, since the port flange and the pipe are separate bodies, thermal deformation is possible and durability is improved. In addition, since the tip of the exhaust port side pipe is a folded flange, the sealing performance is improved. Furthermore, since it is possible to use electric resistance welded pipe for the exhaust port side pipe, cost reduction can also be achieved.

[Brief description of drawings]

FIG. 1 is a fragmentary plan view of an exhaust manifold according to a first embodiment of the present invention.

FIG. 2 is an enlarged view of the main part.

FIG. 3 is an enlarged view of the main part of the second embodiment.

FIG. 4 is a cross-sectional view of a connection portion between a port flange and a pipe in the exhaust manifold of Conventional Example 1.

FIG. 5 is a cross-sectional view of a connection portion between a port flange and a pipe in the exhaust manifold of Conventional Example 2.

[Explanation of symbols]

 1 Cylinder head 2 Port flange 3 Exhaust port side pipe 4 Folding flange 4a Port flange contact side retaining part 4b Folding elastic part 4c Cylinder head contact side seat 5 Gap 10 Exhaust manifold

Claims (1)

[Scope of utility model registration request] 1. An exhaust manifold 10 connecting an exhaust port side pipe 3 to a cylinder head 1 by means of a port flange 2 and a return flange 4 which is turned back at least once at the tip of the exhaust port side pipe 3.
Exhaust manifold characterized by the provision of.